1. Field of the Invention
This invention relates to an apparatus for hyperthermia treatment.
2. Description of the prior Art
Medical practitioners have known that a patient with a cancerous tumor can be successfully treated, by a process which raises the temperature of the tumor. This treatment is generally referred to as hyperthermia. One method of hyperthermia treatment is the use of microwave radiation energy. The temperature of the tissue irradiated by microwave energy is a function of the power or intensity of the microwave signal applied to the surface of the body tissue. The depth of penetration of a microwave signal into the tissue is an inverse function of the signal frequency employed. The volume of the tissue to be treated is controlled by the electrical and geometrical design of the microwave applicator. It is known that a flexible applicator can be utilized to conform to irregular surfaces. Such an applicator is described in U.S. Pat. No. 2,407,690, issued Sept. 17, 1946, to G. E. Southworth as illustrated by FIG. 7 thereof.
It is also known that remission of a tumor can be effected by elevating its temperature to 43.0.degree..+-.0.5.degree. C. It is desirable to provide for an equal temperature distribution within the treated tissue.
Prior methods of hyperthermia treatment employ a microwave-waveguide applicator to supply a microwave signal for the irradiation of the treated tissue. The distribution of the irradiating signal from the microwave-waveguide applicator is manifested as a pattern of standing waves of the operating frequency. The standing wave distribution produces maximum and minimum voltage points which develop non-uniform irradiating signals, correspondingly, producing undesirable non-uniform heating of the treated tissue.